Heat insulating receptacle



Feb. 26, 1952 P. A, SHE 2,586,873

HEAT INSULATING RECEPTACLE INVENTOR ATTORNEY Feb. 26, 1952 P. A. slPLE 2,586,873

HEAT INSULATING RECEPTACLE Filed June 22, 195o 2 SHEETS- SHEET 2 I INVENTOR A? VaulfLlFi@ ATTORNEY Patented Feb. 26, 1952 UNITED STATES PATENT OFFICE HEAT INSULATING 'RECEPTACLE Paul A. Siple, Arlington, Va.

(Granted under @thev act of'March 3, 1883, as amended April 30, 1928; 370 0. G. 757) Claims.

The invention described herein, if patented may be manufactured and Y'used rby or for the Government for governmentalpurposes, without the Ipayment to me of any royalty thereon.

This application is a division of my copending application-Serial No. 595,229, led May 22, 1945', now Patent No.- 2,520,972, datedl September 5, 1950.

My invention relates to heat'insulating receptacles,- and more particularly to a receptacle for enclosing objects to protectl them from flames and intenser-heat so constructed that it may `be permanently or removably secured about the body and including meanssealedY withinits `walls for dissipating the 'heat therefrom under conditions ofA abnormal temperature.

Inthe past various vmeans havebeen devisedV for `protecting-safes,iile cabinets,I mail pouches and otherl receptacles for containing or storing valuables of all kinds against heat and flames In allof thesecoversthe-protection aorded is secured by thermally-insulating the inner storage space lfrom exterior heat, and various constructionsfhavebeen devised forfthis purpose. The Walls of the protective covers may be made from Amaterial of l10W heat conductivity, or a-thermal insulating'material may be disposed intermediate'the inner'land outer walls of the protective container, or a deadair space or -spaces may be provided in these walls or variousv combinations oftthese constructions may be used. Such covers and'containers are effective Vonly to the extent thatY .these specially constructed Walls prevent conduction of heat inwardly, and in `this respect they are often inadequate. Although flamesmay bes-prevented from reaching :the interior compartments, nevertheless, so much heat is vconducted vthrough the V.walls that the objects or mae terials; stored therein are scorched or damaged in other respects by the heat. Theonly means `of preventing thisy is by `increasing the thickness of the walls of the containers, but consideration of factors; .such as thespace available or Ylimits Ion permissible loads may limit thethickness ofV theA walls.` .Y Forexample,1 pouches `for carrying regis.-

teredzmaiL. air mail-,orvaluable `cargoesby train,V shipgor air Aexpressmustnot only belsturdy'and compact:;but also light-z in vveie'htrso that the largest possible pay load ycanbecarriedon each trpzr.. ThCre-rsapractical 'limit to the permis.- sible; wall; thickness; in,k suchcontainers or.

pouches which; if exceeded, destroys the-usefulness of the container;A The protectivecovers'def scribed and claimed thisA application are parapplications. As the descriptionproceeds, it willi be obvious that they are equally adaptable and eiiective for use in protecting stationary storage receptacles such as file cabinets, safes and st0r-V age boxes of all kinds. By making use of my invention it is possible to construct ay heat insu.`

lating protective cover with relatively thin wallsf` because I provide a vaporizable coolant sealed in the walls of the cover or container and releas. able after a predetermined temperature isreached, for absorbing heat from the Wallsof the cover and dissipating it to the `surroundings to prevent its transfer inwardly to the interior of the container. Thus, itis possible to provide ample protection with a relatively thin walled cover. It has been found that covers constructed in accordance with my Ainvention are particulai-ly suitable for use in protecting valuable Vca-rgoes carried by airplanes because in the event the plane crashes and burns the fire, ordinarily,`

is of relative short duration, but the Vheat generated is very intense. Sufficient coolant canbev carried within the walls of my protective cover to prevent the transfer of heat therethrough for the duration of the ii1e. It is, therefore, an ob-l ject of my invention to provide v:a new andim-A` ed in sections and dismountably secured about the receptacle tobe protected to provide all aroundV protection therefor.

Another object of the invention is the provision"Y of the new and improved heat insulating ,cover which has a readily, vaporizable` substance having a high heat of vaporization non-escapablyA sealed within its walls at normal temperatures,

but which is vaporized by abno-rmal external heat...

andas a vapor discharges outwardly from the walls carrying with it the absorbed heat of vaporization which is thereupon'dissipated tothe.'

surroundings. a

Another object of the invention is the provi-y sion of a new and improved heat insulating cover having g laminated walls, including laminations whichnon-escapably retain Va .coolant therein: at normal temperaturesbut which upon r.heating of the :walls -above a Y predetermined temperature" 3 permits the escape of the coolant in vaporized form.

Another object of the invention is the provision of a new and improved heat insulating cover having outer wear resistant Walls and having inner walls for non-escapably retaining a coolant between the outer walls at normal temperatures, the exteriorally facing walls being weakened by abnormal external heat so that rupturing of these walls by the vaporized coolant is promoted and the vapor discharges through the outer walls thereby dissipating the absorbed heat of vaporization.

Another object of the invention is the provision of a new and improved heat insulating cover which is light in weight, durable and compact in construction, inexpensive to manufacture and which may be used in covering objects of various sizes and shapes.

These and other objects of the invention will become apparent from the following description and accompanying drawings in which,

Figure 1 is a front elevational view of my improved cover secured on a le cabinet with the front panel removed to more clearly illustrate the construction and the manner in which my cover is mounted.

Figure 2 is a side elevational view of the protective cover shown in Figure l with a side panel removed. Y

Figure 3 is a top plan View partly in section, of the protective cover shown in Figure 1 with the top panel removed.

Figure 4 is a fragmentary sectional view taken on the line 4-4 of Figure 3.

Figure 5 is a fragmentary sectional view taken on the line 5-5 of Figure 3.

ReferringI to the drawings, in which similar characters of reference indicate similar parts throughout the several views, I have shown by way of illustration in Figures l to 5 a heat insulating cover for a le cabinet incorporating the principle of my invention. The file cabinet II is of standard construction and is surrounded by panels I2 which when assembled for a casing or housing completely enclose the cabinet. Each of these panels has inner and outer walls I3 and I4, respectively, of at sheet metal of suitable thickness to provide a rigid self-supporting wall. The walls I3 and I4 are secured together in spaced relation by means of bolts or rivets I5 which carry a spacing sleeve I6 positioned thereon between the two walls for maintaining the walls in xed spaced relation as shown in Figures 4 and 5. A plurality of thermal insulating pads II are secured in the space between panel walls I3 and I4, four pads of similar construction being shown in the side and end panels. Each of these pads consists of an inner layer of absorbent material I8 completely enclosed or lacketed by a layer of liquid and vapor impermeable material I9. The absorbent layer I8 is saturated with water before the impermeable jacket I9 is sealed about the pad so that each pad forms a unitary water jacket. The pads I'I are of such size that when placed in juxtaposed relation in the panel they completely ov-erlie the inner wall thereof. Any material having high water absorbent properties such as Fiberglas cloth or wool may be used for the absorbent layer I8, and the impermeable jacket is made from a material impermeable to both liquid and vapor at normal temperatures, such as rubber or Vinylite latex or any of the synthetic rubbers or plastics which are impermeable to both liquid and Vapor.

The bolts or rivets I 5 are so spaced in the walls of the panel that they pass between adjacent pad I'I as shown in Figures 4 and 5, and the pads are held in place by a plurality of metal straps 20 extending from top to bottom of the panel. These straps have apertures through which the boltsl5 and sleeves I6 pass, and they are held in snug engagement with the outer face of the pads by means of spacing sleeves or blocks 2| secured on the bolts I5 over the spacing sleeves I5. These blocks 2| bear against the inner side of th-e outer wall I4 of the panel and the outer surface of the strap 20 as most clearly shown in Figures 4 and 5.

If desired a pad or layer of thermal insulating material 22 may be placed between the pads II and the inner wall I3 of the panel I2 to prevent the transfer of heat from the pads I'I to the inner wall of the panel or to the walls of the cabinet, but this insulating layer is not absolutely essential in all cases because the temperature of the inner side of the pads I'I will rarely exceed the boiling point of water, and, except in unusual cases, this degree of temperature will not damage the contents of a file cabinet.

A plurality of vents 23 are provided in the outer walls I4 of each of the panels I2 to permit the escape of vapor from the interior of the panels. A vertically extending ange 24 is formed on each of the vertically extending edges of the outer walls I4 of the side panels of the cover by folding these edges inwardly through an angle of These flanges are secured to the outer edges of the outer walls I4 of the front and rear panels which extend beyond the edges of the inner walls of these panels to engage these anges on the side panels. A plurality of bolts 25 are permanently secured in the ilanges and engage in apertures adjacent the edges of the outer Wall of the front and rear panels of the covering as shown in Figures 2 and 4. Wing nuts 26 are threaded on the outer ends of these bolts and, when tightened, secure the front and back panels to the side panels to form a housing having an open top and bottom.

The top and bottom panels of the covering are of similar construction to the side panels but the outer edges of the outer walls I4 of these panels are folded downwardly to form sides and ends 2'I for these panels, and the free edges of these sides and ends are off-set inwardly as indicated at 28 in Figures 4 and 5 so that these edges of the top and bottom panels are receivable in the open top and bottom of the cov-ering and snugly engage the edges of the outer walls I4 of the front, and side panels I2. If desired, the off-set edges of the top and bottom panels and the adjacent edges of the vertically extending panels may be apertured for the reception of belts for permanently securing the top and bottom panels to the vertically extending front, rear and side panels.

It will be apparent from this description that thepanel construction which I have described provides a protective covering which may be quickly and easily installed about a cabinet or other storage receptacle or dismounted therefrom as desired, and when it becomes necessary to gain access to the interior, the front panel can be quickly removed. The construction described also permits ready dismantling of the separate panels so that the pads I1 may be replaced if vthat becomes desirable or necessary.

When the protective covering described above is subjected to abnormal heat the water in the 5i pads H S` vaporizedand` aS Vtll-prssilr'e-.iii-,-the pads increases the vapor ruptures the"- impermeable walls I9 ofthe pad and escapes to the space in the interior of the panel and from this space to the exterior through the vents' 23 in the walls I4v of the panels. Escaping vapor carries with sorbentmaterial and. said walls enclosing and non-escapa'blysealing said coolant in said lab it the latent heat of vaporization absorb'ed by it in being vaporized and dissipates it to the surroundings. In this manner, heat is carried from the walls of the cover andi'siprevented frombeing conducted inwardly throughthose walls, and, as a` result, the interior compartment of the cover is maintained at a relatively low temperature.V

The walls of the pads I'l may be provided with vents which have Stoppers adapted to be blown out by the vapor in the pad when its pressure exceeds a predetermined amount. Vents of this type may also be used if desired when the pads are provided with exible impermeable walls, but rupturing of the impermeable walls will be facilitated by the action of heat because the heat tends to cause deterioration of these walls so that they are more easily'ruptured. The absorbent layers I8 hold the liquid water after the impermeable walls are ruptured so that it does notleak from the pad.

For certain types of depositories for valuables such as safes or even in file cabinets a thermal insulating means constructed as above described may be built into the walls of the depository or cabinet. If this type of construction is applied to a safe the thermal insulating pads I1 are positioned in the walls of the safe under the outer armor plating of all of the walls including the door, and vents 23 are provided in those walls:`

When the thermal to permit escape of vapor. insulating pads are built into a iile cabinet an outer metallic shell is provided and the pads are secured in the space between the cabinet wall and the shell. A layer of thermal insulating material,

the water to prevent its freezing. Various other modifications may be made in the invention to provide a heat insulating cover for particular objects or for use in special locations or for special purposes. The various specific structures described herein are illustrative only and are not intended to restrict the invention to any of the particular forms described except as limited by the claims included herein.

What I claim as new and desire to secure by Letters Patent is as follows:

1. A heat insulating protective receptacle comprising a plurality of rigid inner and outer walls disposed to form a conined space therebetween, a flexible absorbent material contained in the space within said inner and outer walls for holding a liquid coolant having a high heat of vaporization and vaporizable when abnormal external heat is conducted into the space between said walls, said outer wall being adapted to permit dischargeof vapor therethrough, said vapor P lli sorbent. material at normal temperatures, vat least one of said laminations' being rupturable-under conditions of external heat andinternal vapor pressure, and means for bracing said iiexible absorbent material and said exiblerlaminations and maintaining them in a position surrounding the contents of said receptacle.

2. A heat insulating` protective receptacle comprisinga plurality of panels, each of said panels comprising a first rigid wall and a second' rigid wall disposed to form a confined space therebetween, said first wall facing outside when said panels are assembled, a exible absorbent material contained in the space within said walls for holding a liquid coolant having a high heat of vaporization and vaporizable when abnormal external heat is conducted into the space between said walls, said irst rigid wall being adapted to permit discharge of vapor, said vapor dissipating the absorbed heat of vaporization to the surroundings when escaping and thereby maintaining the interior of said receptacle in a cool condition, and liquidand vapor-impermeable ilexible laminations intermediate said absorbent material and said walls enclosing and non-escapably sealing said coolant in said absorbent material at normal temperatures, at least one of said laminations being rupturable under conditions of external heat and internal vapor pressure, and means for bracing said exible absorbent material and said flexible laminations and maintaining them in a position surrounding the contents of said receptacle; said panels being dismountably secured in edge abutting relation.

' 3. A heat insulating protective panel comprising a pair of spaced rigid walls, one of said walls being apertured to permit discharge of vapor therethrough, a plurality of exible pads retained in the space between said walls, the ag'- gregate area of said pads being substantially coextensive with the area. of said panel, each of said pads comprising ilexible absorbent material for holding a liquid coolant having a high heat of vaporization and vaporizable when abnormal external heat is conducted into the space between said walls, and a liquidand vapor-impermeable flexible envelope enclosing said absorbent material for non-escapably sealing said coolant in said absorbent material at normal temperatures. said envelope being rupturable under conditions of external heat and internal vapor pressure whereby vaporized coolant escapes through said apertured wall and dissipates the absorbed heat Aof vaporization to the outside, and means for bracing said flexible pads and maintaining them in a position parallel to said rigid Walls.

4. A heat insulating protective panel comprising a pair of spaced rigid walls, one of said walls being apertured to permit discharge of vapor therethrough, a plurality of iiexible pads retained in the space between said walls, the aggregate area of said pads being substantially coextensive with the area of said panel, each of said pads comprising flexible absorbent material for holding a liquid coolant having a high heat of vaporization 1 and vaporizable when abnormal external heat is dissipating the absorbed heat of vaporization to conducted into the space between said walls, and a liquidand vapor-impermeable flexible envelope enclosing said absorbent material for nonescapably sealing said coolant in said absorbent material at normal temperatures, said envelope being rupturable under conditions of external heat and internal vapor pressure whereby vaporized coolant escapes through said apertured wall and disslpates the absorbed heat of vaporization to the outside, and means for bracing said flexible pads and maintaining them in a position spaced from said apertured wall.

5. A heat insulating protective knock-down receptacle comprisingv a plurality of panels according to claim 3, at least one of said panels having flanges nteriittingV with the adjacent panels and means for removably securing said flanges to said last-named panels, whereby when said panels are assembled, the contents of said 8. receptacle are surrounded by said pads in substantially contiguous relationship.

Y PAUL A. SIPLE,

REFERENCES CITED Ther following references are of record in the le of this patent:

UNITED STATES PATENTS Date l 

